Rice wine vinegar is one popular ingredient in Asian cooking as it can heighten the flavor of various dishes. Not only that, you can even use it as substitutes in food where you usually use traditional vinegar. You can add it up on salads, dressings, and marinades to give it a different twist.
If you’re curious on how this condiment is made, here’s the process of making rice wine vinegar:
First, you have to know that rice wine and rice wine vinegar are different and both of them can be used when cooking. To make rice wine vinegar, the starting material should be rice wine.
The Rice Wine and Vinegar Making Process
Rice winemaking is an old tradition from rice farmers in some areas of Asia, such as China, Vietnam, and Japan. The process is dated to exist even during the Shang Dynasty where inscriptions were telling a story about how alcoholic drinks are made out of cereals, one of which is probably rice.
First, the rice used when making wine is usually sticky or glutenous rice since it can hold more water compared to other varieties that are typically dry. It will be rinsed and cooked in the usual manner. Once the rice is cooked, it will be transferred to a board or tray. The yeast will then be incorporated in the rice to form a mixture.
It will be transferred to an airtight container. The container will be wrapped with cloth or a heating pad to increase the temperature that will hasten the winemaking process. After a few days or weeks, the by-product of the fermentation process is rice wine. Usually, the process of fermentation works by conversion of sugars derived from the starch found in rice to alcohol.
When making rice wine vinegar, the rice wine still has to go to a chemical process to generate vinegar known as oxidation. Usually, it consists of two steps—First, the alcohol will undergo oxidation which will result in the formation of acetaldehyde. Here, you have to introduce oxygen to the chemical process to occur. However, acetaldehyde is a by-product that can’t be used by the body readily. So it still needs to go through a chemical reaction to be converted to a simpler product which is acetic acid.
During the conversion of alcohol to acetic acid, there should be a catalytic enzyme that will facilitate the conversion process. Usually, you need Acetobacter in the equation to create vinegar. It’s a genus of the acetic acid bacteria that can facilitate the conversion of alcohol to acetic acid.
The traditional process of making rice wine vinegar takes a lot of time before the alcohol turns into acetic acid. The rice wine vinegar that underwent a slow and natural process has a distinct flavor compared to commercially produced rice wine vinegar.
Since more consumers are discovering that rice wine vinegar can elevate the flavor of most dishes, the demand for this condiment is getting high. Through the use of technological innovations, manufacturing rice wine vinegar doesn’t take too much time anymore. There are two methods employed in making rice wine vinegar nowadays:
1. Generator method
Alcohol is placed in vats and allowed to drip into the fillings consisting of wood shavings and charcoal. Oxygen will enter the barrels through the roles on the sides of the barrels or at the bottom. Using air compression, the air is blown through the holes to introduce more oxygen that will speed up the process. The collected liquid on the bottom of the vat is now acetic acid. This method is employed when making balsamic vinegar.
2. Submerged method
This method employs large steel tanks where alcohol is placed. The tanks have pumps attached to the bottom that will introduce air in the solution by pumping air bubbles. Nutrients will also be added so that acetobacters will be more efficient in oxidizing the alcohol in the tanks. The tanks will also be heated to speed up the process of conversion. The temperature is usually set at 26-38 degrees Celsius.
The submerged fermentation process is fast; it can yield acetic acid in a matter of a few hours. This method is most commonly employed in manufacturing companies.
Rice wine vinegar has a distinctly sweet flavor and subtle acidity that makes it a suitable ingredient in many Asian dishes. Before it’s produced, it usually has gone through a lot of processes first from the raw material, rice. The rice will have to be fermented with yeast to generate rice wine. The rice wine will go through the process of oxidation through the use of Acetobacter to give off acetic acid as a by-product.